jhominal

import trio 
from typing import AsyncIterator, Awaitable, Callable, Coroutine, Optional, TypeVar

A = TypeVar("A")
B = TypeVar("B")

async def yield_with_delay(val, delay):
    for i in range(5):
        await trio.sleep(delay)

jhominal

class Transaction {}
class ServiceCharge : Transaction {}
class Sale : Transaction {}

interface IChargable<out T> where T : Transaction
{
    Transaction Charge();
}

jhominal

    class Program
    {
        static void Main(string[] args)
        {
            Console.Out.WriteLine("Main Thread ID: {0}", Thread.CurrentThread.ManagedThreadId);
            PrintCurrentSyncContext();

            DoOpInBgThread();

            Console.Out.WriteLine("Set SyncContext to new");